1. Field of the Disclosure
The present disclosure relates generally to a method and apparatus for controlling a data transmission time point to reduce power consumed in a voice call, and more particularly to a method and apparatus for controlling a data transmission point to reduce power consumed in a voice over long term evolution (VoLTE) call.
2. Description of the Related Art
In the 3rd generation partnership project (3GPP) standard, schemes such as connected disconnection reception (CDRX) and semi-persistent scheduling (SPS) are defined to reduce power consumption in VoLTE. For example, in the case of CDRX, if a base station provides information (e.g., scheduling information) about a period where a terminal does not monitor a downlink channel to the terminal, the terminal may save power during the corresponding period. In addition, in the case of SPS, if a base station semi-persistently sets resources for data transmission and allocates the set resources to a terminal, processes that include the terminal requesting the base station to transmit radio resources may be minimized, thus reducing power consumed by the terminal.
A terminal may achieve optimum power saving when it does not perform both data reception over a downlink and data transmission over an uplink. However, in general, if receiving data over a downlink, the terminal should transmit acknowledge (ACK) information or not acknowledged (NACK) information to the data reception over an uplink. In addition, if transmitting data over an uplink, a terminal should receive ACK/NACK information from a base station. Therefore, although a terminal performs only one of uploading data and downloading data, most modules or functions associated with both downlink and uplink are operated.
If a terminal which performs VoLTE does not achieve synchronization between data transmission and data reception over an uplink and a downlink, although CDRX or SPS is applied, it may be difficult to efficiently save power.